ConfigurableFileCalendarAdapter.java

/**
 * Licensed to Apereo under one or more contributor license agreements. See the NOTICE file
 * distributed with this work for additional information regarding copyright ownership. Apereo
 * licenses this file to you under the Apache License, Version 2.0 (the "License"); you may not use
 * this file except in compliance with the License. You may obtain a copy of the License at the
 * following location:
 *
 * <p>http://www.apache.org/licenses/LICENSE-2.0
 *
 * <p>Unless required by applicable law or agreed to in writing, software distributed under the
 * License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either
 * express or implied. See the License for the specific language governing permissions and
 * limitations under the License.
 */
package org.jasig.portlet.calendar.adapter;

import java.io.IOException;
import java.util.Collections;
import java.util.Set;
import javax.portlet.PortletRequest;
import net.fortuna.ical4j.data.ParserException;
import net.fortuna.ical4j.model.Calendar;
import net.fortuna.ical4j.model.component.VEvent;
import net.fortuna.ical4j.util.Calendars;
import net.sf.ehcache.Cache;
import net.sf.ehcache.Element;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.jasig.portlet.calendar.CalendarConfiguration;
import org.jasig.portlet.calendar.caching.DefaultCacheKeyGeneratorImpl;
import org.jasig.portlet.calendar.caching.ICacheKeyGenerator;
import org.jasig.portlet.calendar.processor.ICalendarContentProcessorImpl;
import org.jasig.portlet.calendar.processor.IContentProcessor;
import org.joda.time.Interval;

public class ConfigurableFileCalendarAdapter extends AbstractCalendarAdapter
    implements ICalendarAdapter {

  protected final Log log = LogFactory.getLog(this.getClass());

  private Cache cache;
  private IContentProcessor contentProcessor = new ICalendarContentProcessorImpl();
  private ICacheKeyGenerator cacheKeyGenerator = new DefaultCacheKeyGeneratorImpl();
  private String cacheKeyPrefix = "default";

  public CalendarEventSet getEvents(
      CalendarConfiguration calendarConfiguration, Interval interval, PortletRequest request)
      throws CalendarException {
    Set<VEvent> events = Collections.emptySet();

    String fileName = calendarConfiguration.getCalendarDefinition().getParameters().get("file");

    // try to get the cached calendar
    String key =
        cacheKeyGenerator.getKey(
            calendarConfiguration, interval, request, cacheKeyPrefix.concat(".").concat(fileName));
    Element cachedElement = this.cache.get(key);
    CalendarEventSet eventSet;
    if (cachedElement == null) {
      // read in the data
      Calendar calendar = retrieveCalendar(fileName);
      // run the stream through the processor
      events = contentProcessor.getEvents(interval, calendar);
      log.debug("contentProcessor found " + events.size() + " events");

      // save the calendar event set to the cache
      eventSet = insertCalendarEventSetIntoCache(this.cache, key, events);
    } else {
      eventSet = (CalendarEventSet) cachedElement.getValue();
    }

    return eventSet;
  }

  protected Calendar retrieveCalendar(String fileName) throws CalendarException {

    if (log.isDebugEnabled()) {
      log.debug("Retrieving calendar " + fileName);
    }

    try {
      return Calendars.load(fileName);

    } catch (ParserException e) {
      log.warn("Error loading iCalendar file feed", e);
      throw new CalendarException("Error fetching iCalendar file feed", e);
    } catch (IOException e) {
      log.warn("Error loading iCalendar file feed", e);
      throw new CalendarException("Error loading iCalendar feed", e);
    } finally {
    }
  }

  public void setCache(Cache cache) {
    this.cache = cache;
  }

  public void setContentProcessor(IContentProcessor contentProcessor) {
    this.contentProcessor = contentProcessor;
  }

  public void setCacheKeyGenerator(ICacheKeyGenerator cacheKeyGenerator) {
    this.cacheKeyGenerator = cacheKeyGenerator;
  }

  public void setCacheKeyPrefix(String cacheKeyPrefix) {
    this.cacheKeyPrefix = cacheKeyPrefix;
  }
}